Most of the time you only need one pump if greased regularly. It kinda easy to figure out when it's needed. Just like others, if you KNOW you plan to use the FEL that day and think its gonna be over an hour of use, grease it up. If you just washed it or came in from the rain,muddy areas, grease it up. Grease pushes the dirt and water out. After a major snowstorm, I grease it up. IMHO, no need to pump till all old grease comes out and have gobs all over, just pump enough to have grease pressure inside so when using the FEL, the new grease gets moved around. The old grease will work it self out anyways.